D - Merge Slimes https://atcoder.jp/contests/abc323/tasks/abc323_d

abc323_d.py

import heapq

N = int(input())
slimes = {}
que = []
for _ in range(N):
    s, c = map(int, input().split())
    slimes[s] = c
    heapq.heappush(que, s)

ans = 0
while que:
    s = heapq.heappop(que)
    c = slimes[s]
    if c == 0:
        continue
    # 合体できない個体
    ans += c % 2
    # 合体してできる個体の数
    nxt_c = c // 2
    if nxt_c > 0:
        nxt_s = 2 * s
        if nxt_s not in slimes:
            slimes[nxt_s] = 0
            heapq.heappush(que, nxt_s)
        slimes[nxt_s] += nxt_c
    slimes[s] = 0

print(ans)